1. Field of the Invention
This invention relates to a method and apparatus for cleaning parts which are components of semiconductor processing equipment and which include surfaces that are directly exposed to the atmosphere in the equipment, which atmosphere extends around a semiconductor wafer or other semiconductor part being processed in the equipment.
More particularly, the invention relates to a method and apparatus for removing both super-micron and sub-micron contaminant particles from the surface of a part from a semiconductor processing apparatus.
In a further respect, the invention relates to a method and apparatus particularly suited to cleaning ceramic parts from a semiconductor processing apparatus.
2. Description of the Prior Art
Equipment like the Lam Research Corporation (LRC) etcher (hereafter "LRC etcher") is widely used in the processing of semiconductor wafers. After a photolithographic pattern is formed or deposited on a semiconductor wafer, the wafer is loaded into an LRC etcher. The LRC etcher utilizes a plasma etching process to remove portions of the wafer which are not protected by the photolithographic pattern. The LRC etcher can be utilized as an oxide etcher, metal etcher, polymer etcher, etc. Such etching of the wafer causes particles of silicon oxide, nitride, arsenic oxide, tungsten oxide, aluminum oxide, titanium, ammonium chloride, chlorine based compounds, and other contaminant materials to be deposited on the surface of parts or components of the LRC etcher which are exposed to the atmosphere surrounding the wafer while the wafer is etched. Since such contaminants can adversely affect the processing of future wafers processed by the LRC etcher, contaminant particles must be carefully cleaned from the surfaces of parts in the LRC etcher, or in other equipment utilized to process semiconductor wafers or components.
One disadvantage of conventional processes of removing contaminant particles from parts used in an LRC etcher or other semiconductor processing equipment is that such processes do not remove most sub-micron particles from the surface of a part, particularly sub-micron particles which have a width of 0.5 to 0.2 micron or smaller. In prior years, the existence of such particles was not a major concern because the lines in the photolithographic patterns were larger and were spaced farther apart. It was only important to remove super-micron particles (i.e., particles with a width equal to or greater than one micron). With time, photolithographic patterns have become finer. The lines are narrower and are spaced closer together. As a result, the ability to remove sub-micron particles (i.e., particles having a width of less than one micron) has become critical. A variety of companies have, since about 1992, been working on the development of equipment for removing sub-micron contaminant particles from the surface of parts found in semiconductor processing equipment. Although such research has significant commercial import, it appears that an economical, reliable, practical process for consistently repeatedly removing a substantial portion of sub-micron contaminant particles from parts in a semiconductor processing apparatus has not yet been developed.
Accordingly, it would be highly desirable to provide an improved method and apparatus for cleaning the surface of a part utilized in semiconductor processing equipment.
It would also be highly desirable to provide in improved method and apparatus for removing sub-micron particles from parts used in processing semiconductor materials.
Therefore, it is a principal object of the instant invention to provide an improved cleaning method and apparatus for parts from semiconductor processing equipment.
Another object of the invention is to provide an improved cleaning method and apparatus for removing contaminant particles from parts having a surface comprised of a ceramic.
A further object of the invention is to provide an improved cleaning method and apparatus for removing sub-micron particles from the surface of a part utilized in processing semiconductor processing equipment.